I was just trying to install Spotify and ran into the problem as described in the OP. After looking around i found that the ebuild for the current latest version (0.9.10.17) -is- available, but it wasn't considered by emerge. I then found out it is only available on ~amd64 (so -not- on ~x86 (the one i regularly use if a package is masked for x86/amd64), let alone any stable keyword).

After installing with ACCEPT_KEYWORDS="~amd64" the latest ebuild (version 0.9.10.17) was used, installed correctly and afterwards provided me a working Spotify-cliënt

I know this thread is a bit old, but it is amongst the most recent threads Google found and I believe this information, although not hard to find out if you're an experienced Gentoo-user, can help out people struggling with the same issue and spare them some time._________________Registered Linux user 355792

spotify is p2p garbage causing pings to go from 20 to 500-1000. that's right, it consumes 100% of upload bandwidth. use the spotify web apps instead, they don't consume absurd quantities of bandwidth. as for gentoo i propose its removed from the tree as it behaves maliciously.

Spotify is moving away from P2P; so, there should be no need to start moving. Other than that, I've never experienced a ping or bandwidth related problem with it; usage of P2P and malicious behaviors are two things apart, you need to actually connect the dots (eg. Does it read from your user's files?) to demonstrate the malicious behavior that you're assuming...